Well, I've decided to give it a crack - here is the reply I received.....
Thank you for your response and photo of incorrect Item you have sent.
As we discussed, I have contacted the
Aqua Gardening on your behalf to advise that the product you received is incorrect as it should be
5L and that the matter be resolved as soon as possible. I have included you in that message to ensure that you are notified when the seller responds.
You can access your messages by logging into your Catch account and clicking on the link below:
https://www.catch.com.au/my-account/messages
We want to reassure you that we’re here for you during this difficult and challenging time.
Again, thank you for your patience and understanding. Should you not hear back from the seller after 2 business days or you’ve got additional questions please let me know so I can personally assist you in raising this to our Specialised Marketplace Team.
Should you have any further queries, please let me know and I will be more than happy to assist you.
Thank you for shopping with Catch, have a lovely day!
Regards,
Moises
Customer Service